fix: Internal debugger crash when instruction would read 2 bytes starting at 0xFFFF#2260
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maximilien-noal merged 1 commit intoJul 13, 2026
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Pull request overview
This PR addresses a crash in the internal debugger’s disassembly operand evaluation when an instruction’s operand evaluation attempts to read past the end of a real-mode segment (e.g., reading a 16-bit value starting at offset 0xFFFF). The change ensures the UI no longer crashes during operand evaluation while paused.
Changes:
- Wrapped operand evaluation in
DisassemblyViewModel.EvaluateOperands()with exception handling to prevent UI crashes. - On evaluation failure, clears/hides evaluated operand values for the affected disassembly line.
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maximilien-noal
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maximilien-noal
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July 13, 2026 19:11
maximilien-noal
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Jul 13, 2026
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@brunom I hit this crash once in a while but forgot about it, nice to see a fix for it! Thanks! |
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When a function exit poped 0xffff into si, an instruction far away that read 16 bits from si made the debugger crash because it extended past the segment end. Now the debugger shows no actual values for that instruction, but should be fixed when it's about to execute and registers have differente values.